Battery help 6v with 8v battery won't start

I picked up a 1949 f1 flathead 6.
Original wiring and all. It has an 8v battery in it.

the battery is fully charged but won't turn the truck over.

I can hook a set of jumpers up to it from my 2004 mini van and it will start right up.

What is wrong. Please help.

Is this a vehicle that you hook the positive to the negative and the positive to the ground??

 

The starter does not care pos or neg ground. You need to check that this is not some sort of 12v starter re-wind you have there OR is that 8v battery good? Do you have a load tester to test battery's? If not get or borrow one and start again...Lol.

 

I just took the battery out and had it tested. Showed 8.1 volts.

How do you ck the starter?

 

does the starter do nothing with the 8v batt? Or does it just crank real slow?
8.1 volts with a voltmeter means nothing, you need a Load placed on the battery while the voltage is measured... Harbor freight has OK cheap load testers... Money WELL spent...

 

The starter can be removed and cleaned up, looking for id marks, etc, something that may indicate "12v" or similar... Next the starter MAY be able to be tested by a local starter re-builder.... if still exist in your area, otherwise TRY a auto parts store where you will likely know more about this old car than they do... frustration. Anyway, next will be a tear-down & inspect brush condition, armature condition & bushing condition... Bad bushings cause the armature to sag in the fields reducing the horsepower of the starter., sometimes they even drag inside the starter... The 12v will overcome these problems, but not that don't fix it...

 

All this ASSUMES that you have good ground connections... between the battery, frame and the motor... Good, Clean connections and cables

 

Yeah what kennkat said.

If you jump the 8 volt battery straight to the starter,
(no solenoid)
does it spin it?

How hot do the wires get?

TP

 

Best as I know, there's no markings to distinguish 12V starters from 6V, but if you pull it out at least you can clean it and bench test it.

The OP hasn't given enough info for a good diagnosis. The truck was originally 6V positive ground, but all that can change in 60+ years.

 

8v battery is an old gimmick for giving a 6 volt system some extra oomph. Probably the last owner put it in because the starter was getting tired. Now the starter is even more tired and it won't respond to 8 volts anymore.

First I would make sure all cables are the right size and all connections clean and tight. Then if the starter is not working, take it off and have it rebuilt. There should be a local auto electric shop that can do this.

By the way your Ford was originally 6v positive ground. In other words, the battery goes in "backwards".

This is too obvious but do you have a solenoid? Is it working correctly?

 

Just to add info, if you replace any big gauge wire from battery to solenoid/ground or solenoid to starter, make sure it is the proper size cable (that means BIG for 6-volt systems). The crap at the local auto parts will barely work for 12-volt let alone 6-volt. The Bigger the better and the end connectors have to be crimped on tight or even soldered if need be. 6-volt worked from the T days all the way to 1955 and did OK until the need for more amperage came along for all the modern amenities. A 6-volt system will not properly charge an 8-volt battery anyway. They will need 9 to 9.5-volts to charge properly and a 6-volt system only puts out 7.5 volts max.

 

Just a possibility, I had a 52 dodge 1 1/2 ton truck and it had 2 6V batteries. One for the standard electrical and the both together for the starter. Sorry for the poor explanation but you can see what I mean. This was in the manual as the stock set up.

 

THIS FIRST !!.............the prior posts are what follows if AFTER you've checked these things there is no improvement.


Ray

 

The key point here is that it will start with a jump from a 12 volt system. This suggests that it might be a 12 volt starter or a 12 volt solenoid that won't make contact with less than 12 volts. Does the starter try to turn with only the 8 volt battery?

 

It also suggests there is sufficient resistance in the circuit (rust, corrosion, etc.) that it takes 12 volts to 'push through' the resistance with enough voltage remaining to run the starter.

Ray

 

Usually the early stuff isn't marked as there was no 12 volt to differentiate from.
Later rebuilds or swaps usually have some kind of stamp.
Although I've only seen a handful stamped 12 volt.
TP

 

What he said....Take the cables loose and clean every connection in the positive cable circuit and the negative cable circuit. An 8 volt battery is just a lazy mans solution to poor connections. I've never seen an 8 V battery. My 41 woody was having intermittent trouble starting. I had a friend turn it over while my head was under the hood and sure enough I saw a spark on the leaving side of the solenoid. I immediately cleaned every connection to and from the battery and the problem was gone. Use a good wire brush and even a file where necessary to get good clean parent metal for a good connection.

12V systems are bad enough with poor connections but 6V systems are much more susceptible to poor connections. If someone has changed the system so that the ground cable goes to the frame instead of the block, move it to the block like it came from the factory. The fewer connections in the system the less likely to have a poor connection.

 

do I hook the positive to the engine and the negative to the solenoid?
Or do I leave it the way it is hooked up.

Positive to (right side as looking at it) solenoid and negative to the top of the engine block?

 

It depends what all the last guy f*cked up. If all he did was put the battery in backwards all you need to do is put it in the right way.

If he also switched the coil connections you need to switch them back.

You may also need to polarize the generator.

A 6V generator will charge an 8V battery if you adjust the regulator to 9.5V. Stock setting is 6.3-6.9 volts to close.

 

was told the generator and starter were just rebuilt. Don't know what to 6v, 8v or 12v.

Is there a wiring diagram for the way it should be wired up properly?

 

An F-1 Ford PU should be positive ground. The + terminal on the battery should go to the engine block. The - terminal should go to the solenoid and another cable down to the starter. Wire brush all these connections. Any poor connection makes it harder to start and they add up. Make sure that they are the larger 6V cables to carry the heavier 6V amperage and have not been replaced with thinner 12V cables from a "bubble pack" parts store. Not sure? order replacement cables meant for your truck from a Ford restoration parts house like Macs. When in doubt order the correct parts. You want it to be reliable like it was when it was new with the correct parts.

 

OK in post #3 you said the battery was 8.1 volts. It is not completely charged. A battery fully charged should be 2.2 volts per cell = 8.8 volts. Put a voltmeter on the battery when you try to crank it. What does it go down to? I bet it gets very low.

As stated before the old trick of using an 8 volt battery in a 6 volt system always caused problems.

 

I don't know if the 8 volt will cause problems. But if you use one to mask problems it will usually be temporary.

I would keep the 8 volt battery, make sure all the wiring was correct, if the starter still did not work I would take it off and fix it or take it to a rebuilder.

Here is a weird one I ran into on a 55 Dodge hemi hardtop. The owner had the starter rebuilt but it still turned over slow. Had problems for years. I took the starter apart and found the rebuilder put 12 volt field coils in it. Had it rebuilt with the correct field coils and it worked perfect.

So, just because it was rebuilt does not mean it was done right. Especially if it was a parts store exchange unit. There are a lot of bad ones. I take mine to a local auto electric rebuilder, I don't even bother with the parts stores. The rebuilder does a better job, uses better parts, and charges about half as much.

 

Where can I aquire a wiring diagram for the truck?

I am thinking I need to start back at ground 0. Make sure everything is wired right. If not fix it. I do see I will need some new wires the originals are frayed a little.

Anyone know where to get a good and easy replacement wiring harness?

 

You still haven't mentioned if you LOAD TESTED the battery. That has been the best starting point advice given, next to the primary checks of connections, grounds, cables, etc.

You have been given the best advice possible, and you are ignoring those who took the time to help you.

Now you are asking about a new wiring harness, be real here. If you are not comprehending the previous post's and GOOD advice, you willl never install a new harness.

There is NO such thing as a " easy replacement " harness, it takes hard work and skill to do correctly. It might seem like I'm picking on you, but I'm not. You need to learn the basics and start with the advice given to you.

 

Heres a bit of real good advice to help you, look in the phone book for Automotive Electric shops, find one and bring the starter to him. Starter Relay too if it has one.

That is of course AFTER you have done, learned, and understood the previous " basics ".

All the best, TR

 

Advanced Auto can test your starter and generator.

 

And if the 1949 starter is bad, they pull one off the shelf right?

This is why you find a Auto-Elec shop from the beginning when you have a 60 plus year old vehicle.

 

My 67 El Camino would not start in the dead of winter. I bought a starter, laid on my back in 20* weather and changed the starter. Turned the key and had the same click click click.... Disconnected the battery terminals, cleaned all the surfaces and started it up and went to work late. That was the last time that I jumped to conclusions. I wasted 50 bucks on a rebuilt starter when all I needed was clean terminals. That was a 12V system too. Not nearly as critical as a 6V system. Two things my cars must do...start easily and stop. I get these systems squared away first. I'll spend a few bucks on good battery cables and connections. I do not like laying on the cold concrete in the winter.

 

No I am not ignoring the advice above. I am looking for a load tester to test the battery. I am also looking at taking the battery back out and get it and the starter tested.

I am currently tracing all the connections and cleaning up the connections to what they connect to. As listed above. Chase the connections and make sure they are making good contact.

While doing that I am finding alot of wires that are exposed and frayed that isn't save. Wires that have been cut and also wires just sitting in space with nothing hooked up to that.

So that is why I have asked about a wiring harness and also a wiring diagram. I don't expect an electric wiring harness to be plug and play. I understand that it will be a large undertaking. I do understand what is listed above and I am looking into some of those problems.

I was also told that sometimes it is easier to replace the wires back to original locations and setup because you don't know who has rigged what where. Easiest step is to start at step 1 wiring harness. In that process you replace what is possibly wrong. Then you take the starter and other electronics and take them to someone that knows electrical and have that tested. Then put them back in.

 

No-o-o-o-o they won't pick one off the shelf but you can find out if it's OK or not then go from there. It costs zip and there is one on every corner.